1. Field of Invention
The invention relates to a plug-in jumper for electrical junction and/or connecting terminals, especially terminal blocks, for elastic engagement in openings in busbars and for electrical contact-making of busbars of at least two junction and/or connecting terminals, with a jumper bar, wherein the jumper bar includes a bar strip and several plugs connected to the bar strip and each plug includes at least two contact legs located essentially parallel to one another, of which at least one is made elastic. In addition, the invention relates to electrical junction and/or connecting terminals, especially terminal blocks, with a housing, with at least one busbar, with at least two connecting elements and with a detachable plug-in jumper.
2. Description of Related Art
Electrical junction and/or connecting terminals, especially terminal blocks, have been known for decades and are used in the millions in the wiring of electrical systems and devices. The terminals are generally locked onto mounting rails which are often located in a plurality in a switchgear cabinet. In terminal blocks, the conductor terminal elements are mainly screw terminals or tension spring terminals. The clamping principle in tension spring terminals is similar to that of screw technology. While in a screw terminal a tension sleeve pulls the conductor against the busbar by actuation of the terminal screw, in a tension spring terminal, this task is assumed by the tension spring. In addition, however, there are also terminal blocks with conductor terminal elements with cutting blades which cut the insulation of the inserted conductor and make contact with the core of the conductor.
Electrical terminal blocks are generally connecting terminals so that they have at least two conductor terminal elements which are electrically connected to one another via an electrically conductive connecting bar, that is, the busbar. These terminal blocks are also called feed-through terminals. In addition to this basic type of terminal block, there is moreover a host of different types of terminal blocks which are specially adapted to the respective applications. Examples here are two-tier, three-tier or four-tier terminals and three-conductor or four-conductor terminals which then each have a correspondingly larger number of conductor terminal elements. Two-tier, three-tier or four-tier terminals which are generally also called tiered terminals, have thus two, three or four busbars which are located on top of one another in different planes and which each electrically connect two conductor terminal elements at a time to one another.
To reduce the wiring cost for terminal blocks which are locked on a mounting rail next to one another, it is known to use plug-in jumpers with a corresponding number of plugs. The plugs of the plug-in jumper are inserted in the corresponding openings in the busbars of the individual terminal blocks, by which the individual busbars or the individual terminal blocks are electrically connected to one another.
The above described conventional plug-in jumper and/or electrical junction and/or connecting terminal is disclosed in, for example, German Patent 44 11 306 C1. The known plug-in jumper is characterized in that it has two jumper bar segments which are located next to one another and on which one contact leg at a time per plug is made, the spring loading of the plug taking place parallel to the lengthwise direction of the bar strip. The two jumper bar sections can be simple stampings so that the known plug-in jumper can be produced very easily.
German Patent application 42 23 540 A1 likewise discloses a plug-in jumper in which however the spring forces of the contact legs upon insertion into the opening of the busbars are aligned transversely to the lengthwise direction of the bar strip. It is however common to the two known plug-in jumpers that they can only be used when the same types of terminal blocks are arranged in a row next to one another. For example, with these plug-in jumpers several identical feed-through terminals can be electrically connected to one another.
German Patent 195 33 992 C1 discloses an electrical tiered terminal with two busbars which are located on top of one another, in which an electrical connection of the two busbars is possible by means of a plug-in jumper having only one plug which can be inserted into the two plug openings which are flush with one another in the busbars. In particular, the known plug-in jumper consists of two spring contacts which adjoin one another flat and which, in the area of their top contact zone which interacts with the upper busbar, have offsets pointed in opposite directions to one another. When the plug-in jumper is inserted into the two openings of the two busbars, this leads to elastic spreading of the two spring contacts in the opening of the top and the bottom busbar. The spreading takes place in opposite directions resulting in the plug-in jumper making contact with the two busbars. Thus an electrical connection of two busbars of a terminal block can be accomplished by this known plug-in jumper.